Petroleum Refinery Automates Case & Pail Palletizing

A petroleum refinery needed to increase production speeds to match demand for their products, but were restricted by the palletizing stage of production. Furthermore, employees were loading the products onto the pallets by hand, putting them at risk of injury due to heavy lifting and repetitive motions. The optimal solution would keep their employees safe while making their lines more efficient. Automation would provide these benefits.

The petroleum refinery had two different product types, cases of varying sizes and 20-liter plastic pails. With limited space and resources, it was important that the system could handle both lines simultaneously. An innovative approach would be required to compensate for the differences in their packaging.

The automation system would also have to account for the discrepancy in the case sizes. While only one case size ran at a time, the need for changeovers to a different size required that the system be capable of handling different case sizes on demand, in addition to the pails. This necessity for flexibility suggested the use of a robot with a sophisticated end of arm tooling design.

Seeking a solution, the company attended Pack Expo, where they saw Flexicell’s booth displaying their automation systems. The petroleum refinery saw firsthand the expertise displayed by Flexicell on the tradeshow floor, and were impressed by the experience Flexicell already had with overcoming similar problems. The following shows how Flexicell met all of the requirements above and more.

Solution

The case and pails are brought to the robot cell by two Hytrol conveyors which are equipped with Hytrol’s EZ Logic to provide buffering and zero back pressure. Once within the cell the products are collated onto a custom-built positioning conveyor. From there a Fanuc M410iB/160 Palletizing Robot palletizes them in pairs.

The robot is equipped with an end of arm tooling (EOAT) that has both vacuum grippers for the cases and mechanical jaws for the pails. The controller can switch the robot between the two methods depending on which product group is ready for palletization.

The EOAT uses patented servo-powered technology to adjust to case size. During a changeover, the operator selects the case size using the custom-built HMI, which directs the independent vacuum zones on the EOAT to move to match the size selected. The system is ready to go within seconds.

The robot arranges the products on the pallets until they are the correct height. Pallet loads are automatically moved out of the cell by heavy drag-chain conveyors. An empty pallet is then released from the pallet magazine via conveyor until it is within the robot’s work envelope. The robot uses mechanical fingers on the EOAT to pick and place the pallet into the empty loading position.

The next phase is stretch-wrapping of the pallet load. The company’s prior method for stretch-wrapping was to move the pallet via forklift to where it could be wrapped. When Flexicell personnel visited the company’s facility, they saw an opportunity to improve the production line even further by integrating an automatic stretch wrapper into the palletizing system. This would reduce manual handling even further. By implementing this, the result was a palletizing process automated from start to finish.

Like all systems, safety fencing was installed around the robot cell. By using light curtains, dual safety check software, and safety door switches, the system immediately stops the robot if people enter.

By integrating the robot, conveyors, stretch-wrapping station, and safety guard, Flexicell has provided a safer, more efficient palletizing system. Flexicell’s commitment to quality has ensured that it exceeded the company’s initial expectations in performance and reliability.

The project manager at the refinery said: “Flexicell is the best [vendor] I have personally dealt with. [They] are good at customer service, and of course, great at what [they] specialize in...the designing of robot applications. I would recommend [them] to anyone.”